| 摘要 |
PURPOSE:To obtain the measurement results corresponding to actual use state by detecting the generation condition of the cracks produced by local heating of an object to be examined with laser beam of >=500W output and >=3mm. beam diameter, by means of acoustic emission signals. CONSTITUTION:Gaseous argon is sealed in a test vessel 4 made of acrylic resin, and is maintained inert, then a test piece 1 is placed on a stand 5 for test piece. A signal is derived from an AE (acoustic emission) converter 10 via a waveguide 9 made of alumina mounted at one end of the test specimen. The laser beam from a laser beam source 6 is irradiated via a mirror 7 and a lens 8 to the test piece 1 to heat or cool the same rapidly. The output of the laser beam souce is >=500W, and the beam diameter is >=3mm. which are set in accordance with the kinds and sizes of the test pieces. If the time since the test piece is heated until a cracking is generated, the cycle of the heating and cooling, and the stability and unstability of the cracking and detected by means of the AE signal, the test of superior reproducibility in the use condition equivalent to the actual use condition is executed with simple equipment. |
